Medical Marijuana News, is legal hemp about to ruin america’s outdoor cannabis crops?Concern that pollen from industrial hemp farms could end up ruining nearby cannabis crops is hardly new. In a 2003 paper titled “A Preliminary Study of Pollen Dispersal in Cannabis Sativa,” researchers with Agri-Food in Canada (where commercial hemp farming has been federally licensed since 1998) examined the risk. Published in the Journal of Industrial Hemp, their investigation began with the earliest known identification of the problem, dating back more than 300 years.

“In 1694 Rudolf Jacob Camerer wrote a scientific letter concerning the first experimental evidence of sex in plants. Camerer noted that careful removal of male plants from a field of dioecious hemp did not completely deter production of fertile seed, and he commented that he was “quite upset” at the observation, obviously caused by hemp pollen from distant sources. In modern times, long-distance pollination is of great concern because of the possibility of genetic contamination.”

The paper also noted that in nature, hemp is almost exclusively wind-pollinated. Since it gets little to no help in this regard from bees—which love to collect the plant’s pollen, but are not attracted to its female flowers—cannabis has evolved a strategy of releasing large clouds of pollen that are capable of traveling great distances.

A single hemp flower can generate about 350,000 individual pollen grains, with a large hemp plant producing hundreds of such flowers. All of this pollen can spread out for up to 30 miles on a steady breeze, putting any female cannabis plant within that radius at risk.

In 2000, when hemp cultivation remained prohibited throughout the United States, a study tested the air in the Midwest (where hundreds of millions of feral “ditch weed” hemp plants grow) and found that in mid-August hemp pollen represented up to 36% of the total airborne pollen count.

“It’s Rope, Not Dope!”
Weed and hemp are really the same plant—scientifically known as Cannabis sativa—but represent two distinctly different genetic lineages of that species, selectively bred over thousands of years for very different traits. Which explains why so much of the hemp movement’s support has traditionally come from the cannabis community.

Though back in the day, not everybody returned the favor. In fact, some activists touted hemp’s lack of a high as a major selling point. “It’s rope, not dope!” was a common refrain among this crowd.
The irony being that in many US states, legal weed growers actually got a big head start on hemp farmers. California became the first state to approve the cultivation of medicinal cannabis in 1996. Colorado and Washington were the first states to approve “recreational” cannabis in 2012.

Meanwhile, the federal ban on hemp cultivation remained firmly in place until the 2014 Farm Bill passed, and that only allowed limited crops in a small number of states for research purposes. In 2018, just 77,000 acres were planted nationwide. But that number will likely skyrocket this year after the most recent Farm Bill removed basically all remaining federal impediments, leaving regulation of the once banned agricultural commodity up to individual states.

In Oregon, this has already led to a turf war.

The Crux of the Problem
The crux of the problem is that once a female cannabis plant is pollinated, it begins producing seeds instead of producing more psychoactive resin, resulting in a harvest of low-potency seed-laden buds that nobody this side of 1976 will want to buy. This is why high-THC cannabis cultivators either start with “cuttings,” to ensure an all female crop, or grow from seed, but then carefully cull out all of the male plants as soon as they show their sex.

Hemp grown for CBD is also ideally an all-female sinsemilla (Spanish for “without seeds”) crop, making it equally susceptible to pollen drift.